That, would not surprise me, coming from an Ultra power supply known to have poor internal build quality.
I wouldn't be willing to say that for sure, that's the deal, but I sure wouldn't rule it out either.
Thermaltake isn't much better, on a LOT of their power supply models, BUT the Toughpower series models are generally anywhere from decent to very good. The Toughpower grand units especially are generally really good. Coming in a prebuilt, I'd probably assume it's not a toughpower grand model, but one of the lesser Toughpower models. Any chance you can take a look at the label and find the exact model of that unit?
Being as you recently built this, I have to ask, are you 100% positive that when you installed it there were ONLY the exact number of motherboard standoffs installed in motherboard tray on the case that were needed for that ATX form factor? Previously you didn't have a micro ATX motherboard, or some other form factor, and that all standoffs that were installed lined exactly up with the mounting holes in your motherboard. Every last one? With no extras or any that seemed out of place? Because that's a pretty common problem for inexperienced builders and I've even seen experienced builders good up there and short the board out on a standoff in the wrong place OR forget entirely to use standoffs and short out the board on the case itself.
Also, no chance of any bent pins on the CPU?
I think it would be a good idea to read my guide on motherboard bench testing, and follow the steps there, but again, I would not use that Ultra PSU, at all. Use the Thermaltake while testing. Even if it's not a great model, and it might be, it's got to be better than that Ultra.
Finding the problem through bench testing If you are here then it’s likely you have encountered a serious hardware issue and have been unable to resolve it using the standard no-POST troubleshooting procedures. If you have not yet attempted to resolve your issues using the no-POST...
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